1. a) Are the following systems CAUSAL?
y(n) = x(n) + 0.25 x(n-1) + 0.5 x(n-2)
y(n) = x(n+1) – 0.5 x(n-1) + 0.8 x(n-1)
b) What is the number of multiplications required for performing the convolution of two sequences with identical length 8 using the direct method?
c) What are the special addressing modes in Programmable DSPs?
d) What are the various units present in TMS32OCX CPU?
e) What is the use of guard bits in accumulators?
f) Which of the following instructions has an operand of length 3-bits in
TMS32OC54X DSP? LLD #05,ARP AND #1234h,A,A
g) What are pipeline latencies in C54X DSP?

2 .a) Determine the impulse response coefficients of a digital LP filter with H (ejw)=1, for
ω < ωc and, H (ejw)=0 for ω < ωc < π
b) Show how the computational complexity of an FIR filter of order 21 can be reduced by using three polyphase filters.

3 .a) Disitinguish among Von Neumann, Harward and Modified Harward architecture for the computer. Which architecture is preferred for DSp applications and why?
b) Explain the operation of TDM serial ports in Programmable DSPs.

4. Explain the internal architecture of TMS32OC3X using its functional block diagram.